Conventionally, there is known a feeding mechanism 900 for sheet staple, which is arranged underneath a cartridge (not shown) in which sheet staples ST are stacked and contained, as shown in FIGS. 13 and 14.
The feeding mechanism 900 is composed of a ratchet plate 901 extending forwardly and backwardly, a feeding pawl 910, a spring guide 920, a feeding spring 930 for biasing forwardly the ratchet plate 901 and so on. A leading end of the ratchet plate 901 is formed with an inclined surface 902 and a concave portion (not shown) of a driver 350 is abutted with the inclined surface 902.
As the concave portion is abutted with the inclined surface 902 of the ratchet plate 901 by upward movement of the driver 350, the ratchet plate 901 is moved backwardly (rightward) against a biasing force of the feeding spring 930 as the driver 350 moves upwardly.
As the ratchet plate 901 is moved backwardly, the feeding pawl 910 is fallen down as shown in FIG. 15. This fall down of feeding pawl is carried out by the feeding pawl 910 being rotated centering on a hole 904 of the ratchet plate 901 in counterclockwise.
As driving of the sheet staple S is completed by the upward movement of the driver 350, and the driver 350 and a forming plate 351 are lowered in an initial position, the spring guide 920 urges forwardly the feeding pawl 910 by means of a biasing force of the feeding spring 930.
At this time, the feeding pawl 910 is raised up by means of the inclined surface 922 of the spring guide 920 as shown in FIG. 13. In other words, from such a state that a clearance is generated between the feeding pawl 910 and the inclined surface 922 of the spring guide 920 as shown in FIG. 15, the feeding pawl 910 is in surface contact with the inclined surface 922 of the spring guide 920 so as to eliminate the clearance as shown in FIG. 13.
As the ratchet plate 901 moves forwardly together with the spring guide 920 by the biasing force of the feeding spring 930, a pawl part 911 of the raised feeding pawl 910 is inserted between the staples in the sheet staples ST. Consequently, the feeding pawl 910 feeds out forwardly each of the sheet staples ST according to the movement of the ratchet plate 901.
However, because the aforementioned feeding mechanism 900 for sheet staple is composed of the ratchet plate 901, feeding pawl 910, spring guide 920, feeding spring 930 and so on, there is a problem that a great number of parts are required.
An object of the present invention is to provide a feeding mechanism for sheet staple capable of minimizing the number of parts.